Transition metal complexes of polyarylene oxides and sulfides

ABSTRACT

Polyarylene oxides and sulfides which are π-arene complexed with transition metals are disclosed. Also disclosed is a process for making a polyarylene sulfide by reaction of a π-arene complexed arylene dihalide with the dianion of an arylene dithiol. The complexed polymers are soluble in common organic solvents, and the polymer solutions can be used to make films and coatings or to encapsulate parts.

FIELD OF THE INVENTION

Disclosed are selected transition metal complexes of polyarylene oxidesand sulfides which are made by the reaction of a transition metalcomplex of an arylene dihalide with a salt of an aromatic diol or anaromatic dithiol. The resulting complexed polymers are soluble inorganic solvents and can be used to prepare protective films.

TECHNICAL BACKGROUND

Aromatic dihalides form π-arene complexes with certain transition metalgroups such as Cr(CO)₃, RuCp^(*+) (Cp⁺ is pentamethylcyclopentadiene)and FeCp⁺ (Cp is cyclopentadiene). The π-arene complexes sometimessurvive when the aromatic dihalide is reacted.

J. A. Segal, J. Chem. Soc., Chem. Commun., Vol. 198, p. 1338-1339 (1985)reports that p-dichlorobenzene complexed with RuCp⁺ PF₆ ⁻ can be reactedwith the sodium or potassium salts of bisphenol A or his(4-hydroxyphenyl) ketone to form ruthenium complexed PEEK or polyetherof bisphenol A and hydroquinone. No mention is made of forming polymerscontaining sulfur or of polymers in which ether linkages connect all thearylene groups.

A. Alemagna, et al., J. Org. Chem., Vol. 48 (1983), p. 3114-3116 reportthe reaction of chromium complexed arylene dihalides with thiols.Similarly, D. Astruc in Tet. Lett., Vol. 39 (1983) at p. 4069 reportsthe reaction of an iron complexed aryl halide with a phenyl thiolateanion. Ruthenium complexes of aryl halides are similarly reported toreact with thiols in R. M. Moriarty, et al., J. Organometal. Chem., Vol.350 (1988) at p. 173. However, these references do not report polymerformation.

SUMMARY OF THE INVENTION

This invention concerns a transition metal complexed polymer comprisingrepeat units of the formula ##STR1## wherein: each Ar¹ and Ar² isindependently arylene;

M is an iron, chromium, manganese or ruthenium moiety capable of forminga π-arene complex with Ar¹ ; and

each Z is independently oxygen or sulfur.

This invention also concerns a process for the production of atransition metal complexed polyarylene sulfide, comprising, contactingin solution an arylene dihalide π-arene complex with a transition metalcontaining moiety, with a dianion of the formula --S--Ar¹ --S--, whereinAr¹ is arylene.

DETAILS OF THE INVENTION

This invention concerns polymers and a process for making some of thosepolymers wherein there are arylene groups. By an "arylene group" hereinis meant a group with two free valencies to aromatic carbon atoms whichcontains one or more carbocyclic aromatic rings. If more than one ringis present, such zings are fused together and/or connected by a covalentbond. In all of the arylene compounds herein, it is preferred if the"free" valencies are not ortho to each other. Preferred arylene groupsherein are phenylene, biphenylene, and naphthylene. Especially preferredgroups are 1,4-phenylene and 4,4'-biphenylene. Most preferred is1,4-phenylene. Another preferred arylene group is one in which the freevalencies are linear or colinear with respect to one another.

Preferred iron, chromium and ruthenium moieties which form a π-arenecomplex with arylene dihalides and polyarylene oxides and sulfides areCr(CO)₃, RuCp*X, RuCpX, FeCp*X, FeCpX, and Mn(CO)₃ X, wherein X is ananion. Preferred moieties are Cr(CO)₃, RuCpX, FeCp*X RuCp*X and FeCpX.An especially preferred moiety is RuCp*X. The choice of the anion, X, isnot critical

π-Arene complexes of iron, ruthenium and chromium are known, see forexample: R. P. A. Sneeden, Organochromium Compounds, Academic Press, NewYork, 1975, p.19-20 and other portions of this S. G. Davies,Organotransition Metal Chemistry Applications to Organic Synthesis,Pergamon Press, 1982, p. 68-72; and R. M. Moriarty, et. al., J.Organometal. Chem., Vol. 350, (1958), p. 157-190.

In those π-arene complexes herein that contain anions, it is preferredthat the anions be relatively nonnucleophilic. Such anions are usuallythe anions of strong conjugate acids in which the negative charge can bedelocalized over more than one atom. Suitable anions includehexafluorophosphate, triflate (trifluoromethanesulfonate),tetraphenylborate, and chloride.

In the polymerization process claimed herein, a transition metal π-arenecomplex of an arylene dihalide is reacted with an alkali metal salt ofthe dianion of dihydroxy aromatic compound (a diphenol) or an arylenedithiol, or with a compound containing an arylene group which is bondedto one thiol and one hydroxy group [this would give a repeat unitcontaining both sulfur and oxygen in the main polymer chain, i.e., apoly(etherthioether) ]. Both the diphenol and dithiol (and their alkalimetal salts) contain an arylene group, and preferred arylene groups areas described above.

An arylene dihalide is also used, and preferred arylene groups for thiscompound are also as described above. Preferred halogens in the arylenedihalide are fluorine and chlorine. Chlorine is especially preferred.Thus, the preferred starting materials for the polymerization processwill be those diphenols, arylene dithiols and dihalides that correspondto the combination of the above arylene groups with 2 hydroxy groups or2 thiol groups or 2 halogen atoms. The most preferred diphenol ishydroquinone, the most preferred dithiol is 1,4-benzenedithiol and themost preferred arylene dihalide is 1,4-dichlorobenzene. Other preferredstarting materials (and repeat units derived from them) will be apparentto the art skilled, by similar combination of preferred arylene groupsand --OH, --SH and halogens. Preferred alkali metals for the salts ofthe dithiol or diphenol are sodium and potassium.

The polymerization process is carried out in solution. Preferredsolvents are aprotic solvents with relatively high polarity such asdimethylsulfoxide (DMSO) , N, N-dimethylformamide (DMF) ,N-methylpyrrlidone (NMP) and N,N-dimethylacetamide (DMAC). Although thetemperature is not critical, the polymerization can be carried out atabout 25° C. to about 80° C., wherein convenient polymerization ratesare obtained, and under which little decomposition of the startingmaterials and/or product occurs. Mild agitation is preferred to mix theingredients. Where the starting materials and/or polymer product aresensitive to oxygen and/or water, it is convenient to carry out thereaction under an inert gas such as nitrogen or argon.

The complexed polymers produced by this process are usually soluble inaprotic polar organic solvents such as DMSO, DMF, NMP and DMAC. Many ofthe uncomplexed polymers such as polyphenylene oxide and polyphenylenesulfide are not soluble in common organic solvents. Therefore, the useof the soluble transition metal complexes allows these polymers to beused for encapsulating parts such as electronic boards by dipping, andto be used for known processes for making films and coatings from thesepolymers. In the uncomplexed form these polymers are difficult orimpossible to use in such ways. Such encapsulants, films and coatings,particularly in the uncomplexed from (the π-arene complex is decomposedfor example) have good thermal stability and are solvent resistant.

It is believed that the uncomplexed polymers can be obtained from thecomplexed polymers by a variety of methods. For ruthenium and ironcomplexes, methods described by J. A. Segal, supra, which is herebyincluded by reference, can be used. Chromium carbonyl π-arene complexesmay be decomposed by heating to about 250° C. or more, by exposure toiodine (preferably in solution), or by heating in pyridine at 115° C.for about 2 days.

The following abbreviations are used in the examples:

    ______________________________________                                        Cp*         pentamethylcyclopentadiene                                        DCB-Ru      (1,4-dichlorobenzene)RuCp*, SO.sub.3 CF.sub.3                     DCB-Fe      (1,4-dichlorobenzene)FeCp, PF.sub.6                               DMSO        dimethylsulfoxide                                                 DMF         N,N-dimethylformamide                                             ______________________________________                                    

EXAMPLE 1 Synthesis of Ru complexed Poly(phenylene sulfide) ##STR2##

In a nitrogen flushed glove box, DCB-Ru (1.00 g, 1.88 mmol) anddipotassium 1,4-benzenedithiol (0.410 g, 1.88 mmol) were charged into anoven dried 10 mL flask equipped with a stirring bar. Anhydrous DMSO(3.00 g) was weighed into a vial, and this was the total quantity ofsolvent used for the polymerization (ca. 32% solids). The DMSO was addedto the solid reagents, and the reaction was allowed to stir at 60°-265°C. for 2 h. The viscous tan colored solution was diluted with DMSO (ca.3 mL), and the polymer was isolated and purified by precipitation intowater. After filtration, the polymer was dried in a vacuum oven at75°-85° C. for at least 2 h.

Characterization ¹ H NMR (d₆ -DMSO) 7.59 (s, 4H, Ar H), 6.10 (s, 4H,arene), 1.92 (s, 15H, CH₃) ppm; ¹³ C NMR (d₆ -DMSO) 133.3, 132.1, 100.4,97.1, 88.7, 9.5 ppm. Inherent viscosity (0.5%, DMF, 30° C.): 1.21 dL/g.Anal. Calcd for C₂₃ H₂₃ O₃ S₃ F₃ Ru: C, 45.91, H, 4.07. Found: C, 45.08;H, 3.91.

EXAMPLE 2 Synthesis of Ru complexed Poly(biphenylene sulfide) ##STR3##

In a nitrogen flushed glove box, DCB-Ru (0.30 g, 0.564 mmol) anddipotassium 4,4'-biphenyldithiol (0.166 g, 0.564 mmol) were charged intoan oven dried 10 mL flask equipped with a stirring bar. Anhydrous DMSO(1.09 g) was weighed into a vial, and this was the total quantity ofsolvent used for the polymerization (ca. 30% solids). The DMSO was addedto the solid reagents, and the reaction was allowed to stir at 60°-65°C. for 2 h. The viscous solution was diluted with DMSO (ca. 2 mL), andthe polymer was isolated and purified by precipitation into water. Afterfiltration, the polymer was dried in a vacuum oven at 75°-85° C. for atleast 24 h.

Characterization ¹ H NMR (d₆ -DMSO) 7.83 (d, 4H, J=8.1 Hz, Ar H),7.63(d, 4H, J=8.0 Hz, Ar H), 6.06 (s, 4H, arene), 1.92 (s, 15H, CH₃)ppm; ¹³ C NMR (d₆ -DMSO) 139.4, 133.4, 130.1, 128.1, 101.9, 96.8, 87.9,9.5 ppm. Inherent viscosity (0.5%, DMF, 30° C.): 1.38 dL/g. Anal. Calcdfor C₂₉ H₂₇ O₃ S₃ F₃ Ru: C, 51.39, H, 4.02. Found: C, 50.53; H, 4.11.

EXAMPLE 3 Synthesis of Ru complexed Poly(phenylene oxide) ##STR4##

In a nitrogen flushed glove box, DCB-Ru (0.30 g, 0.564 mmol) anddipotassium 1,4-dihydroxybenzene (0.105 g, 0.564 mmol) were charged intoan oven dried 10 mL flask equipped with a stirring bar. Anhydrous DMSO(0.95 g) was weighed into a vial, and this was the total quantity ofsolvent used for the polymerization (ca. 30% solids). The DMSO was addedto the solid reagents, and the reaction was allowed to stir at 60°-65°C. for 2 h. The viscous solution was diluted with DMSO (ca. 2 mL), andthe polymer was isolated and purified by precipitation into water. Afterfiltration, the polymer was dried in a vacuum oven at 75°-85° C. for atleast 24 h.

Characterization ¹ H NMR (d₆ -DMSO) 7.29 (s, 4H, Ar H), 6.13 (s, 4H,arene), 1.97 (s, 15H, CH3) ppm; ¹³ C NMR (d₆ -DMSO) 151.7, 127.0, 120.9,96.3, 78.7, 9.8 ppm. Inherent viscosity (0.5% , DMF, 30° C.): 0.81 dL/g.Anal. Calcd for C₂₃ H₂₃ O₅ SF₃ Ru: C, 48.50, H, 4.07. Found: C, 47.41;H, 4.09.

EXAMPLE 4 ##STR5##

In a nitrogen flushed glove box, DCB-Ru (0.30 g, 0.564 mmol) anddipotassium 4,4'-dihydroxybiphenyl (0.148 g, 0.564 mmol) were chargedinto an oven dried 10 mL flask equipped with a stirring bar. AnhydrousDMSO (1.07 g) was weighed into a vial, and this was the total quantityof solvent used for the polymerization (ca. 30% solids). The DMSO wasadded to the solid reagents, and the reaction was allowed to stir at60°-65° C. for 2 h. The viscous solution was diluted with DMSO (ca. 2mL), and the polymer was isolated and purified by precipitation intowater. After filtration, the polymer was dried in a vacuum oven at75°-85° C. for at least 24 h.

Characterization ¹ H NMR (d₆ -DMSO) 7.79 (d, 4H, J=8.5 Hz, Ar H), 7.30(d, 4H, J=8.6 Hz, Ar H), 6.18 (s, 4H, arene), 2.00 (s, 15H, CH3) ppm; ¹³C NMR (d₆ -DMSO) 154.6, 135.8, 128.4, 126.7, 119.2, 96.3, 79.1, 9.8 ppm.Inherent viscosity (0.5%, DMF, 30° C.): 1.19 dL/g. Anal. Calcd for C₂₉H₂₇ O₅ SF₃ Ru: C, 53.95, H, 4.21. Found: C, 53.09; H, 4.28.

EXAMPLE 5 Synthesis of Fe complexed Poly(phenylene sulfide) ##STR6##

In a nitrogen flushed glove box, DCB-Fe (0.350 g, 0.848 mmol) anddipotassium 1,4-benzenedithiol (0.185 g, 0.848 mmol) were charged intoan oven dried 10 mL flask equipped with a stirring bar. Anhydrous DMSO(1.10 g) was weighed into a vial, and this was the total quantity ofsolvent used for the polymerization (ca. 32.7% solids). The DMSO wasadded to the solid reagents, and the reaction was allowed to stir atroom temperature for 2-3 h. The viscous brown colored solution wasdiluted with DMSO (ca. 2 mL), and the polymer was isolated and purifiedby precipitation into a mixed solvent system of water/methanol. Afterfiltration, the polymer was dried in a vacuum oven at 75°-85° C. for atleast 24 h.

Characterization ¹ H NMR (d₆ -DMSO) 7.7 (br s, 4H, Ar H), 6.4 (br s, 4H,arene), 5.1 (br s, 5H, Cp) ppm; Inherent viscosity (0.5%, DMF, 30° C.):0.42 dL/g.

EXAMPLE 6 Decomplexation of Ru complexed Poly(phenylene sulfide)

Method A.

A dilute d₆ -DMSO solution of Ru complexed poly(phenylene sulfide) washeated at 150°-160° C. for 10-15 h. Decomplexation, monitored by ¹ HNMR, proceeded to ca. 60-70% and was coupled with precipitation of theinsoluble product poly(phenylene sulfide).

Method B.

A dilute d₅ -pyridine solution of Ru complexed poly(phenylene sulfide)was heated at 110°-115° C. for 20-25 h. Decomplexation, monitored by ¹ HNMR, proceeded to ca. 70-85% and was coupled with precipitation of theinsoluble product poly(phenylene sulfide).

What is claimed is:
 1. A transition metal complexed polymer consisting essentially of repeat units of the formula ##STR7## wherein: each Ar¹ and Ar² is independently arylene, wherein arylene is a group with two free valencies to aromatic carbon atoms with contains one or more carbocyclic aromatic rings;M is an iron, chromium, manganese or ruthenium moiety capable of forming a π-arene complex with A¹ ; and each Z is independently oxygen or sulfur.
 2. The polymer as recited in claim 1 wherein Z is sulfur.
 3. The polymer as recited in claim 1 wherein Ar¹ and Ar² are selected from the group consisting of phenylene, biphenylene and naphthylene.
 4. The polymer as recited in claim 1 wherein Ar¹ and Ar² are selected from the group consisting of 1,4-phenylene and 4,4'-biphenylene.
 5. The polymer as recited in claim 1 wherein Ar¹ and Ar² are 1,4-phenylene.
 6. The polymer as recited in claim 1 wherein M is selected from the group consisting of Cr(CO)₃, Ru (pentamethylcyclopentadiene)X, Ru (cyclopentadiene)X, Fe (pentamethylcyclopentadiene)X; Fe (cyclopentadiene) X, and Mn (CO)₃ X, wherein X is an anion.
 7. The polymer as recited in claim 1 wherein M is selected from the group consisting of Cr(CO)₃, Ru(pentamethylcyclopentadiene)X, and Fe(cyclopentadiene)X, wherein X is an anion.
 8. The polymer as recited in claim 5 wherein M is Ru(pentamethylcyclopentadiene)X, wherein X is an anion. 